Circumstances often arise wherein a desire or necessity exists for the collection and separate containment of samples of a liquid. As one example, bacterial urinalysis typically requires the collection of a flow of what is generally termed “mid-stream” urine, as described below.
The best mid-stream urine specimen for bacteriologic diagnostic examination is obtained directly from a patient's urinary bladder by catheterization, or by following a very rigorous 10-step body cleaning technique using various antiseptic agents presently available in wide varieties of mid-stream urinary collection systems. Generally, these tedious and highly intimidating cleaning procedures are not strictly followed due to ignorance or non-acceptance, especially by younger female patients.
Added to the facts of inadequacy in the cleaning process and heretofore unavailability of a competent collection system capable of capturing and isolate the mid-stream urinary specimen, a high incidences of “false positive” diagnostic results has always remained a pit-fall in clinical urinary tract infection management.
The initial part of a patient's urinary flow is called fore-stream urine. In females, in particular, this fore-stream urine, while flowing through a poorly cleaned external urogenital tract, is always regarded as contaminated and unsuitable for urinalysis, especially for microbiological or bacteriological examination. More often than not, the fore-stream urine contaminants produce a high incidence of false positive lab test results that are unfortunately derived from external contaminants located around the external urogenital anatomic parts. These apparently “innocent” false contaminants are dragged along the apparently clean urinary stream from the bladder during its excretion process. When this unintentionally contaminated fore-stream urine, while “rinsing” through the patient's urogenital pathway, is collected in a conventional single chamber collection container and then mixes with the later cleaner, mid-stream sample, such badly mixed mid-stream sample is regarded as unsuitable or unacceptable for lab diagnosis procedures.
A problem associated with such mid-stream urine collection is the assuring of an appropriate cleansing fore-stream urine flow (which is not used for the bacteriological analysis). If the fore-stream urine flow is too small, it will result in inadequate rinsing of the urogenital pathway, and the subsequently collected mid-stream urine flow may be contaminated, thereby adversely affecting the bacterial urinalysis. On the other hand, if the fore-stream urine flow is too large, the patient may produce a mid-stream urine flow quantitatively insufficient for urinalysis purposes (typically 6 ml to 12 ml required).
Heretofore, to the knowledge of the present inventors, the most commonly used mid-stream urine collection procedure requires that the patient continuously urinate into a commode (or other receptacle) an amount of about 30 ml to 50 ml of urine (which will be discarded) estimated as sufficient to rinse the anatomical pathway and provide a cleaner specimen for the required uncontaminated mid-stream urine flow, and then finish urinating into a container to collect the subsequent urine flow for analysis. In such a procedure, the amount of discharged fore-stream urine is usually difficult to control for females, and if too small, may result in a contaminated mid-stream urine flow and if too large may result in too small a mid-stream urine flow for accurate biological analysis. Moreover, such a procedure involves the patient uninterrupting her (or his) urine flow to collect the mid-stream flow—something that may be difficult for collecting the mid-stream urine flow. In any event, such a procedure may result in unintended, unsanitary urination onto the patient's hand and/or the urine collection container.
Therefore, it is highly desirable to provide a device which automatically collects, as a first sample, a predetermined amount of fore-stream urine flow and then automatically collects, as a second, separate sample, a mid-stream urine flow. It is further important that the collection device completely isolates the second, clean mid-stream urine sample from the first tore-stream urine sample to prevent contamination of the mid-stream urine sample.
Another example of the need for collecting two contemporary separate urine samples from the same individual is for drug testing of the individual. Particularly when legal issues are or may be involved, two contemporaneous samples of urine from an individual being drug tested are usually desired, if not legally required. A first one of these urine samples is used for on spot drug testing; the second one of the urine samples is (or should be) maintained in a tamper-proof, preserved condition for subsequent drug testing in the event the on spot drug testing results are contested, for example, in a legal dispute, and a second drug test is required.
It is, therefore, a principal objective of the present invention to provide a dual liquid, particularly urine, sample receiving and retaining device, in which the two samples are isolated from one another.